Friday, January 24, 2014

progress report on the Landing Light

OK, just wanted you all to know that I’m still here!  The garage was unavailable for work for about a week due to another family project that needed the space, so that put me one week out of commission.  When I decided to wait for a new lens (see below), I elected to shelve the Right wing and resume work on the Left.  I had halted work on the Left wing when I was debating E-LSA vs. EAB (2nd landing light and AOA sensor.  After fighting with the damn light all this time, I have no desire to try to install a matching one on the right, so there’s no more reason to put off working on the 1st wing.  See subsequent posts!)  In fact, I got a bunch of stuff done this week and have a few posts (of progress) that will be following this one.  The landing light is still giving me fits, or more precisely, lack of fit.  To wit...


IMG 0151 2

First Fitting of Landing Light Assembly


OK, not so good.  There’s a pucker on the inside edge of both the top & bottom.  I posted this on VAF and got some good feedback, including a correct assessment that the hole looks crappy because I tried to cut too close with the tin snips.  The dimples are too shallow.  I asked if it was possible to install this as described, and I was told that if you squeeze gently, the lens can be inserted through the leading edge opening and just forward of the light itself and thus can be installed from the front.  I still have my doubts.

Feedback about the dimples being too shallow caused me to review my assumptions.  I assumed that I had the correct size dimple based on the claim from Cleveland Tools, but I realized that I needed a #6 dimple to properly set #6 screws.  OK, a week later I have #6 dimple dies and work progressed a little bit.  Following another thread of advice, I very gently elongated some of the holes (< 1 mm) based on the direction that the screws canted when just barely started in the nut plates.  There was also matching sanding/filing of the corresponding holes in the Lexan.  With those tweaks, the front looks better (it will never be nice, but it is getting towards acceptable).

IMG 2877

Second Fitting of Landing Light



IMG 2880

Landing Light Lens with Unacceptable Gap.

When I looked from the side, I was very dismayed to see the huge (3/8”) gap between the Lexan and the skin.  This isn’t anything that I can manipulate any further.   This is after verification than I have the optimum orientation (the curvature of the lens is not symmetric, and it’s a much worse fit when placed upside down).   A VAF commenter said that he had the same problem and was going to heat-soften another piece of Lexan and actually form fit it into the leading edge.  That sounds like a good plan for me.  I just received my replacement Lexan before I came to work tonight.  I’ll experiment with the 1st lens and some scrap Lexan I saved from its initial trimming and make one more attempt to get a better fit.  I’ve spent enough time on this:  Once I get something that is airworthy, I’m going to accept it and move on to the rest of the plane.

No comments:

Post a Comment